Exhaust systems are widely known and used with combustion engines. Typically, an exhaust system includes exhaust tubes that convey hot exhaust gases from the engine to other exhaust system components, such as mufflers, resonators, etc. Mufflers and resonators include acoustic chambers that cancel out sound waves carried by the exhaust gases.
One common problem with exhaust system components, such as a muffler for example, is metallic noise that emanates from the muffler during cool down. The metallic noise is often referred to as a pinging or ticking sound. The muffler includes tubes that are supported by internal muffler structures. When the exhaust system heats up during vehicle operation, the tubes experience thermal expansion, which causes mating surfaces between the tubes and associated internal structures to fit more tightly against each other. When the vehicle is turned off, the exhaust system components cool down and the metallic noise is generated when the mating surfaces release. This release of strain energy caused by the differential thermal expansion of the tubes relative to the internal muffler structures is also referred to as a “stick and release” noise. The components become “stuck” together during thermal expansion, and then when the components are “released” from each other during cool down, the metallic noise is generated.
Therefore, there is a need to provide an exhaust component configuration that reduces noise generated during cool down. This invention addresses those needs while avoiding the shortcomings and drawbacks of the prior art.